Dry joint aluminum wall panel attachment system

ABSTRACT

The invention provides a dry joint wall panel attachment system, applying the rainscreen principle. Interlocking components are used to attach aluminum wall panels to an exterior wall.

FIELD OF THE INVENTION

The invention relates to wall panel systems, and more particularly tomethods of attaching wall panels to exterior surfaces.

BACKGROUND OF THE INVENTION

There are numerous problems with known aluminum wall panel attachmentsystems. Conventionally, such systems relied upon adhesive or caulk to“seal” the aluminum panel from the elements. However, under heat andcold and moisture, the adhesive or caulk breaks down compromising thestability of the system and giving an undesirable appearance. Even whensuch a seal is functional, there a tendency for undesirable effects onthe aluminum panels as the interior environment can trap heat whichaffects the panels, creating “oil-canning” or popping in response to thepressure differential. In spite of such seals, such systems can alsotrap moisture in the wall cavity, which results in oxidation of partsand staining or deterioration of exterior wall surfaces.

More recently systems have been developed according to the “rainscreenprinciple” in which the wall cavity is vented, resulting in atemperature and pressure equalized system with adequate moisturedrainage. However, such systems can be difficult to install, relying onmany components to be milled or adapted on-site, and requiring excessivelabour cost and specialty materials. No suitable system has beendeveloped which applies the rainscreen principle, while providingcost-effective simple installation.

SUMMARY OF THE INVENTION

A dry joint aluminum wall panel attachment system is provided. Thesystem comprises

a bracket assembly fastened to the exterior wall;

an attachment clip fastened to the bracket assembly by a fastener, theattachment clip having a central fastening surface fastened to thebracket assembly and at least one wing member extending outwardly fromthe central fastening surface;

a wall panel having an exterior flat surface and at least two sidesurfaces bent generally perpendicularly to the exterior flat surface anddefining a hollow interior portion;

a panel perimeter strip fastened to one side surface of the wall panel,the perimeter strip comprising:

-   -   a generally C shaped body member sitting inside a corner of the        wall panel and extending along an inside portion of the side        surface, and    -   a receiving member integrally attached to the body member that        extends beyond the side surface of the wall panel and provides a        slot adapted to engage and interlock the wing member of the        attachment clip, thus connecting the wall panel to the        attachment clip and thereby to the wall;

an infill strip dimensioned to fit in the slot of the panel perimeterstrip proximate to the attachment clip so as to cover the fastener;

wherein the system is held together non-adhesively and wherein the wallpanels are ventilated to permit ingress and egress of air and moistureto provide a pressure-balanced and moisture-drained interiorenvironment.

Preferably, the attachment clip (here aluminum) comprises two wingmembers, each adapted to engage a panel perimeter strip of an adjacentwall panel.

Preferably, the bracket assembly (here steel) comprises two back-to-backL angle brackets fastened to each other to form a generally Z shapedassembly, a first end of which is for attachment to the wall and asecond end of which is for fastening to the attachment clip (such as athreaded fastener).

The wall panels comprise an aluminum composite material, which ispreferably routed and bent to form the exterior and side surfaces. Thepanel perimeter strip (here aluminum) may be pre-assembled to the wallpanel before installation to the wall. Preferably the panel perimeterstrip is fastened to the wall panel by rivet. This rivet may contributeto the ventilation of the panel system.

The infill strip (here aluminum composite) may be engaged with the slotof the panel perimeter strip prior to installing an adjacent wall panel.Alternatively, the infill strip may be introduced to the slots of twoadjacent panel perimeter strips after two adjacent wall panels have beeninstalled.

Preferably, the system further comprises an isolation tape which isapplied between the attachment clip and the bracket assembly.

The system may further comprise a panel stiffener component placedinside the hollow interior portion of the wall panel to reinforce theexterior surface of the panel and prevent deforming or popping of thewall panel.

BRIEF DESCRIPTION OF THE FIGURES

So that the manner in which the above recited features of the presentinvention can be better understood, certain drawings are appendedhereto. It is to be noted, however, that the appended drawingsillustrate only selected embodiments of the inventions and are thereforenot to be considered limiting of scope, for the inventions may admit toother equally effective embodiments and applications.

FIG. 1 shows a simplified cut-through view of the dry joint aluminumwall panel attachment system, according to the preferred embodiment.

FIG. 2 shows a panel perimeter strip used in the attachment system.

FIG. 3 shows an attachment clip used in the attachment system.

FIG. 4 shows a cut-through view of a panel stiffener optionally used inthe attachment system.

FIG. 5 shows a cut-through view of the aluminum composite material (ACM)used in the panels.

FIGS. 6, 7, 8 show progressive steps in the formation of an ACM panelfor use in the present system.

FIG. 9 shows a cut-through view of an infill strip used in theattachment system.

FIG. 10 shows a detailed view of the preferred placement of the infillstrip in the attachment system.

FIG. 11 shows a simplified elevational view of the sub-framing usedbefore mounting the ACM panels in the present system.

FIG. 12 shows a detailed view of the complete attachment system withsub-framing.

FIGS. 13, 14, 15 show progressive steps in the installation of panels inthe present system (first method).

FIG. 16 shows a view of the installation of lengths of infill strip inthe present system (second method).

FIG. 17 shows a view of a finished wall paneled exterior.

FIG. 18 shows a cut-through view of an alternative panel perimeterstrip.

FIGS. 19-20 show cut-through views of two versions of an alternativepanel stiffener.

DETAILED DESCRIPTION

The present panel attachment system 10 uses an extruded aluminumattachment system for fastening fabricated panels to all buildingsurfaces. The system's strength is further enhanced by the use of anextruded perimeter frame design.

The system 10 is designed to the standard of the rainscreen principle.Simply, it is designed so that the wall cavity is vented, resulting in apressure equalized system as seen in FIG. 1. Controlled moisturedrainage within the system, coupled with this equalized pressure,contributes to effective, maintenance free construction.

The extrusion process begins with an aluminum billet, the material fromwhich the profiles are extruded. The billet must be softened by heatprior to extrusion process. The heated billet is placed into theextrusion press, a powerful hydraulic device wherein a ram pushes adummy block that forces the softened metal through a precision opening,known as a die, to produce the required shapes. The extruded shape mayhave a mill or anodized finish.

The system includes a panel perimeter strip 14 (FIG. 2), which isattached to the ACM panel 32 using counter sunk rivets 36. The panelperimeter strip is designed to fit together with the attachment clip 16(FIG. 3). The custom designed extrusion allows for maximum attachmentarea without foregoing structural integrity.

The attachment clip 16 (FIG. 3) is used on site to attach the panelperimeter strip 14 to the building as illustrated in FIG. 12. The clip16 is designed so as to interlock with the panel perimeter strip 14while holding the infill strip 38 (FIG. 10) securely in place.

The system optionally includes a panel stiffener 18 component (FIG. 4),which may be used on large sized panels. The stiffener 18 is used toprevent the popping or “oil canning” of the panel. As the panel heatsup, the panel expands and makes a popping sound. The stiffener 18reinforces the panel to reduce this effect.

The panel stiffener 18 may comprise a hollow tube, as shown in FIG. 4.An internally reinforced panel stiffener 18A, 18B may alternatively beused for greater stability (see FIGS. 19, 20). Where panel stiffenersare used, the panel perimeter strip may be adapted to better locate andsecure the stiffener component. A panel perimeter strip 14A havingprofile as shown in FIG. 18 may be advantageous for this purpose. Theextended interior lip of the panel perimeter strip operates to securethe panel stiffener component.

Panel stiffeners may be provided in different sizes depending on thewind pressures to which the panel will be exposed. A larger width panelstiffener 18B may be advantageous where there are greater wind loads onthe panel system or if less deflection on the panel is desired. It willbe appreciated that the construction of the panels also provides a basiclevel of rigidity and stiffeners are not necessarily required.

As shown in FIG. 5, the aluminum composite material 20 (ACM) consists ofa core of low density polyethylene 24 sandwiched between two sheets ofaluminum 22 (each approximately 0.5 mm thick). The finish face of thealuminum is coated with a polyvinylidene fluoride coating. The inneraluminum layer is typically coated with chrome or polyester coatings.The standard thickness of the panel is 5/32″ (4 mm) but thickness mayrange from ⅛″ (3 mm) to ¼″ (6 mm), depending on customer preference orstructural requirements.

A finished ACM panel 32 may be fabricated from a flat sheet of ACM 26using different types of router and cutting bits 28 (FIG. 6). After thesheet of ACM has been cut and routed, it is then bent along the routerlines to form the finished panel 32 (FIG. 7). The newly shaped panel 32is then assembled with the panel perimeter strip 14 using a panel rivet36 to complete the finished panel (FIG. 8). A standard panel rivet forthis application is 3/16″ diameter.

There are various methods to accomplish the routing and cutting process:

Method 1

Handheld router (not shown): A handheld router is used more often whenreworking a panel to a different size. This method requires the simplesttool set up, but is the most labour-intensive method of fabrication dueto the lengthy time for setup and layout of each different panel.

Method 2

Vertical table saw (not shown): A vertical table saw can also be used,both to cut and rout the panels. Custom “V” routing blades can bepurchased to rout the panels. Panel design is limited using the verticaltable saw in itself. Using it in combination with the hand held routerhas its advantages, but it is still a costly way to manufacture panels.

Method 3

CNC-Machine (not shown): The computer numerically controlled (CNC)machine is a complete and concise way to manufacture panels. Once thepanel has been designed by a CAD operator it is then sent directly tothe machine. This machine has been found to be very useful andeconomical for manufacturing panels. This is the applicants' preferredmethod for cutting and routing panels.

The infill strip (FIG. 9) is typically cut to a width of approximately1¼″ (32 mm) for a ½″ (13 mm) joint. The infill strip replaces theconventional caulk joint, giving the panel system a clean, maintenancefree appearance. The infill strip also is used to hide the fasteners 36for the attachment clip (FIG. 10).

As shown in FIG. 11, to install the panel system, sub framing is firstconstructed using two back-to-back galvanized steel “L” angles 40 (FIG.12); the two “L” angles allow the installer to level the substrate inall 3 axes before installation of panels. The sub framing is typicallyinstalled horizontally at each horizontal joint as shown in FIG. 11. Themethod of installation of the framing at its correct installationmeasurements starts at the bottom of the substrate wall and moves up,making sure that each row is level to the previous row installed.

A layer of isolation tape 42 may be applied to the back of aluminumattachment clips 16 (FIG. 3) to prevent direct contact between thegalvanized steel sub framing and the aluminum attachment clip and thusprevent galvanic action (electrolytic decay of the aluminum) over time.Preferably, stainless steel self-drilling screws are used to fastenaluminum attachment clips to steel sub framing 40. After determining alogical order of installation, each panel is to be plumbed and leveledto ensure a tight and concise fit form panel to panel.

Infill strip is preferably shipped in long lengths and are to be cut tofit on site. The strips may have a protective plastic coating, which isthen removed from the face of the infill strips before installing them.These infill strips can be installed one or two ways:

First, as shown in FIGS. 13-15, the infill strips may be slipped inbefore the adjacent panel is installed when the edge of the joint is notaccessible, or when the infill strip has a curve or bend in it. Theinfill strip 38 is fitted into the space between the panel 32 return andthe attachment clips 14 as illustrated in FIG. 13 and FIG. 14. Then anadjacent panel 32′ is installed so that the infill strip 38 andattachment clip 16 engage into the slots in the panel edge at theperimeter strip 14′ (FIG. 15).

As an alternative method of installation, the installer can slide theinfill strip 38 in from the end (FIG. 16), which allows for a simplifiedinstallation of the panels. The infill strips are not installed until anarea is complete. This means that panels can be adjusted forstraightness and position even after adjacent panels have beeninstalled. The difficulty with this method is that the end of the jointwill not always be accessible (i.e. wall or window frame) and the infillstrip 38 may have a tendency to catch on the attachment clips as it isbeing slid into the joint. To aid in the sliding of the strip, a toolmay be used to pull the leading edge over the clips (not shown).

The finish faces of the panels may have a protective film 50 to protectagainst minor abrasions that may occur during handling and installation.The protective film may be peeled back from the returns of the panelsbefore installing. To keep the panels clean and free of constructiondebris, generally the protective plastic film 50 is only removed fromthe faces of the panels once the landscaping has been completed, as seenin FIG. 17.

The foregoing description illustrates only certain preferred embodimentsof the invention. The invention is not limited to the foregoingexamples. That is, persons skilled in the art will appreciate andunderstand that modifications and variations are, or will be, possibleto utilize and carry out the teachings of the invention describedherein. Accordingly, all suitable modifications, variations andequivalents may be resorted to, and such modifications, variations andequivalents are intended to fall within the scope of the invention asdescribed and within the scope of the claims.

1. A dry joint aluminum wall panel attachment system for attaching awall panel to an exterior building wall, the system comprising: abracket assembly fastened to the exterior wall; an attachment clipfastened to the bracket assembly by a fastener, the attachment cliphaving a central fastening surface fastened to the bracket assembly andat least one wing member extending outwardly from the central fasteningsurface; a wall panel having an exterior flat surface and at least twoside surfaces bent generally perpendicularly to the exterior flatsurface and defining a hollow interior portion; a panel perimeter stripfastened to one side surface of the wall panel, the perimeter stripcomprising: a generally C shaped body member sitting inside a corner ofthe wall panel and extending along an inside portion of the sidesurface, and a receiving member integrally attached to the body memberthat extends beyond the side surface of the wall panel and provides aslot adapted to engage and interlock the wing member of the attachmentclip, thus connecting the wall panel to the attachment clip and therebyto the wall; an infill strip dimensioned to fit in the slot of the panelperimeter strip proximate to the attachment clip so as to cover thefastener; wherein the system is held together non-adhesively and whereinthe wall panels are ventilated to permit ingress and egress of air andmoisture to provide a pressure-balanced and moisture-drained interiorenvironment.
 2. The attachment system of claim 1, wherein the attachmentclip comprises two wing members, each adapted to engage a panelperimeter strip of an adjacent wall panel.
 3. The attachment system ofclaim 1, wherein the bracket assembly comprises two back-to-back L anglebrackets fastened to each other to form a generally Z shaped assembly, afirst end of which is for attachment to the wall and a second end ofwhich is for fastening to the attachment clip.
 4. The attachment systemof claim 1, wherein the wall panels comprise an aluminum compositematerial.
 5. The attachment system of claim 1, wherein the wall panelscomprise an aluminum composite material which is routed and bent to formthe exterior and side surfaces.
 6. The attachment system of claim 1,wherein the fastener comprises a threaded fastener.
 7. The attachmentsystem of claim 1, wherein the panel perimeter strip is pre-assembled tothe wall panel before installation to the wall.
 8. The attachment systemof claim 1, wherein the panel perimeter strip is fastened to the wallpanel by rivet.
 9. The attachment system of claim 8, wherein the rivetcontributes to the ventilation of the panel system.
 10. The attachmentsystem of claim 1, wherein the infill strip is engaged with the slot ofthe panel perimeter strip prior to installing an adjacent wall panel.11. The attachment system of claim 1, wherein the infill strip isintroduced to the slots of two adjacent panel perimeter strips after twoadjacent wall panels have been installed.
 12. The attachment system ofclaim 1, wherein the system further comprises an isolation tape which isapplied between the attachment clip and the bracket assembly.
 13. Theattachment system of claim 1, wherein the attachment clip comprises analuminum attachment clip.
 14. The attachment system of claim 1, whereinthe bracket assembly comprises a steel bracket assembly.
 15. Theattachment system of claim 1, wherein the infill strip comprises a stripof aluminum composite material.
 16. The attachment system of claim 1,wherein the panel perimeter strip is made of aluminum.
 17. Theattachment system of claim 1, wherein the system further comprises apanel stiffener component placed inside the hollow interior portion ofthe wall panel to reinforce the exterior surface of the panel andprevent deforming or popping of the wall panel.